"Actually it's not a silly idea," Rachel said.
"It's not easy to find 'fake' glasses for kids, and these really do protect young eyes from light that can be harmful to them."
Stella, with strong support from her mum, had had the choice of "dipping her toe into the water" or leaping right in.
"We've leapt right in," she added.
The process had been a valuable educational experience for her daughter too. She had designed the frame, a mould had been made and dispatched to China for manufacturing, costs had had to be calculated, packaging designed and costed, and a marketing campaign organised.
"It's been an amazing experience," Rachel said.
Stella had also conducted a good deal of research, including surveying her school mates before deciding on the colour range, and had become adept at the art of the spreadsheet.
She had also had significant help from friends who were experts in various fields, and had been happy to give her a hand. And while she had been involved in much of the process of turning an idea into a marketable product, at heart she was the "design queen," and very much the public face of the enterprise.
"She's very entrepreneurial," Rachel added, "and she really does seem to have latched on to something here."
The glasses are selling via the website at $69.95 for the limited edition gold-with-glitter version, and the others for $59.95, each box inviting the purchaser to share a selfie via @stellavisioneyewear